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50 Year Birthday of the Number One Electronic Switching System

Started by unbeldi, June 13, 2015, 01:18:05 PM

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unbeldi

Before the date once again slips into the hole of forgotten history...
did anyone celebrate the noteworthy 50th birthday of the No. 1 Electronic Switching System?


On 30 May 1965 the first 1ESS telephone exchange was cut into commercial operation in Succasunna, New Jersey, a very small central office serving a community of ca. 4300 residents.

Succasunna is located on the eastern edge of the NJ foothills of the Pocono mountains of Pennsylvania, a car hour west of New York City, and within just a few miles west on State Route 10 from the Bell Laboratories facilities in Whippany.

The Whippany location was previously the development center for the Electronic Central Office, the experimental forerunner of the ESS, installed for a trial in Morris, Illinois during 1960, and operating until 1962 (see http://www.classicrotaryphones.com/forum/index.php?topic=12748.msg133997#msg133997). I believe, however, that the No 1 ESS was principally developed a bit further away in the Holmdel, NJ, location.

Physical construction of the Succasunna ESS apparently started in 1963, only a short time after the Morris conclusion.  Undoubtedly, the technical and strategic development was well under way even before the Morris trial.  The Morris system planning started about a decade before the actual event. The system validated the concept of electronic switching and laid out some parameters that were incorporated into the design of the ESS. A notable feature of the Morris system, the audible tone signaling system for ringing telephones and for automatic number identification was abandoned in favor of the conventional local loop design with electro-mechanical high-voltage ringing.

At the time, the development of the ESS was the largest sustained effort ever in the Bell System towards a single goal [W.A. Mac Nair, AT&T BLR 49(6)], and this likely remained to be true at the time of Bell System deconstruction twenty years later.

In essence, I think, the history of development in telephonic switching may perhaps be characterized most comprehensively in terms of the concepts of separating the actions of the local, detailed operations that interconnect two communicating telephones from the higher-level concepts that control such goals. While progress in material science, mechanical engineering, and manufacturing methodologies delivered constantly improving piece parts, these advancements laid a foundation for the higher-level aspects of system design.

Most prominently today, this includes the developments that followed the era of the Bell System in the US and the equivalent technologies in Europe (Ericsson, Siemens, etc.) or Japan, namely the technologies of packet-switching in the Internet.

It is probably no coincidence in the grand theme that the breakup of the Bell System pretty much coincided with the breakthrough of the TCP/IP protocol suite—enabled on the ARPANET on January 1, 1983—from an experimental system to the production technology that empowered the emerging Internet. It created the exact opposite of the monopolistic marketplaces of the Bell era.  Today, voice-over-Internet Protocol (VOIP) technologies present the highest level of abstraction, or separation, of control and action in telephony—and not only there—in essence rendering obsolete many long-standing concepts, including numbering plans, area codes, office codes, even the very existence of telephone numbers.

This abstraction in telephone switching from direct control of the early step-by-step machines in which the network was principally involved in the decision making, started perhaps with the registers and senders of the Panel system in the 1910s. By 1965, through generations of crossbar switches, the Electronic Switching System had taken much of the network out of the process. Yet, it represented only a snapshot of the development.

Unlike all previous technology developments in switching, which involved preselection of previous proven systems, where a preferred technology existed, the electronically switched office was based on new unproven concepts. New technologies had to be developed at various stages to achieve similar goals but by different means. Common control did not happen in an instant.

The first instantiation of production electronic switching was actually the 101ESS, but it was not a central office switch. It was a large private branch exchange system that divided operation between separate subunits installed in the enterprise and other parts installed at the central office. The cross-point switch resided in the enterprise units, while call control and trunking happened in the central office units.  The system introduced time-division multiplexing (TDM) for internal communication.

The 1ESS shared many concepts and components with the 101ESS, but the TDM switching of the 101 it did not have in common.  The 1ESS was still based on space-division switching. One common theme starting with the Morris system was the principle of common control. The promise of the high switching capacity of electronic components based in part on semiconductor technology, including the transistor, and the advent of large and fast digital storage memories, allowed the concentration of all system logic into a single central subsystem, controlled by a (computer) program located in central memory storage. Miniaturization of components provided 'high density' circuit packs, printed circuit boards (PCB), that could be installed in modular fashion, speeding up debugging and repair cycles.

1ESS featured a capacity of up to 65,000 lines, with a switching capacity of 100,000 calls per hour.  The Succasunna office started out with only 200 customers. The second 1ESS central office was constructed the following year in Maryland.  By 1974 AT&T had installed a total of 475 systems with over 5 1/2 million lines.


I had intended a larger article for the occasion, this is an extract, to serve as a history marker.  A few weeks ago, I stopped by the Succasunna office and took some pictures for posterity.


==Some References==
*Bell Laboratories Record, Volume 49 (6), June 1965
*AT&T Archives: Electronic Central Office Debut in Succasunna, NJ, 1965
*Kempster Miller (1933, McGraw) Telephone Theory and Practice—Automatic Switching and Auxiliary Equipment, The Panel Dial System, pp183.




unbeldi

The central office in 1965.

The AT&T archives have a wonderful film clip of the opening of this office:

AT&T Archives: Electronic Central Office Debut in Succasunna, NJ, 1965



unbeldi

Succasunna April 2015.

The office still serves only four prefixes in area code 973:  252  584  598  927

Its 2L-5N designation was JUstice 4 (584), which at the time was located in area code 201. I don't know if other office names were used before ANC.

Today, the building (SUCCNJSU) houses a WECo 5ESS.

RotarDad

Thanks Unbeldi for another excellent piece of history and for sharing your knowledge.   I really like the building pics - what caught my eye is that computers don't need windows, so they were removed.  Amazing what has happened in the past 50 years as technology advances.  The next 50 will be mind-blowing I'm sure.   I've read that some experts see the "Singularity" coming by 2050, where all the technology converges and radically changes the human experience...... who knows?
Paul

unbeldi

Quote from: RotarDad on June 13, 2015, 02:21:23 PM
Thanks Unbeldi for another excellent piece of history and for sharing your knowledge.   I really like the building pics - what caught my eye is that computers don't need windows, so they were removed.  Amazing what has happened in the past 50 years as technology advances.  The next 50 will be mind-blowing I'm sure.   I've read that some experts see the "Singularity" coming by 2050, where all the technology converges and radically changes the human experience...... who knows?

Thanks.
Yes, the only other opening of that structure to the outside world is shown in this picture.
From the pictures of 1965 and 2015, it is even evident that the 1965 glass front was reduced with solid fillers to just the width of the front door, albeit still glass today.

The product  of the structure flows in and out via conduits in the ground, as may be inferred from the second snapshot.


unbeldi

When viewing the AT&T video, one should take notice of the amazing technology of the ESS:
In the film clip at time 2:15 one of the engineers or operators places a telephone call using a hand-cranked magneto telephone!

Amazing.

AE_Collector

#6
Unbeldi:

I just now found and read this topic from a link you placed in the "49 500 set at the San Jose Show" topic.

http://www.classicrotaryphones.com/forum/index.php?topic=15258.0

Very nicely written and illustrated documentation of the first ever 1ESS office put into service. I enjoy reading about CO conversions and "firsts" make it even better.

I have some information on Automatic Electric Canada's first Electronic CO switch, the "C1", (predecessor to the #1EAX) that was built at AE Canada in Brockville Ontario and installed in a field test at a SxS CO about 25 miles from where I live and then removed again for further analysis back at Brockville. This was around 1968 or 1969. I will try to put a topic together about it on CRPF.

Thanks again for all if this information about Succasunna.

Terry